Lane change device

Abstract

To provide a lane change device capable of surely completing a lane change of an own vehicle even when there is a following vehicle approaching the own vehicle at a high speed.SOLUTION: A lane change device 10 executes lane change control for causing an own vehicle 100 to change lanes to an adjacent lane. The lane change device is configured to: estimate a following vehicle catching-up possibility that a following vehicle 200R, which is traveling so as to approach an own vehicle from behind the own vehicle and is traveling on the adjacent lane to which the own vehicle performs lane change by the lane change control, may catch up the own vehicle; set a target lane change time, which is a target time from when the lane change of the own vehicle is started by the lane change control to when the lane change to the adjacent lane is completed, to a shorter time as the following vehicle catching-up possibility is higher; and perform lane change to the adjacent lane of the own vehicle by the lane change control so as to complete the lane change to the adjacent lane within the set target lane change time.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to a lane change device.

Background Art

[0002] There is known a lane change device that automatically changes the lane of the host vehicle to an adjacent lane. Also, there is known a lane change device in which a time (lane change time) from the start to the completion of the lane change of the host vehicle is set in order to complete the lane change of the host vehicle within a certain time. Further, as such a lane change device, when there is a vehicle (following vehicle) traveling while approaching the host vehicle in the adjacent lane in which the host vehicle is about to change lanes, in order to reduce the driver's sense of uneasiness of the host vehicle with respect to the lane change of the host vehicle or to safely perform the lane change of the host vehicle, there is also known a lane change device configured to change the lane change time (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] Conventional lane change devices are configured to detect the following vehicle based on information obtained from a radar sensor, a camera sensor, etc. mounted on the host vehicle. However, due to reasons such as the detection and detection capabilities of the radar sensor, the camera sensor, etc., when the following vehicle is traveling at a place far from the host vehicle, it may not be possible to detect the following vehicle. And when the following vehicle approaches the host vehicle at high speed, if the lane change of the host vehicle is started just because the following vehicle is not detected, the following vehicle may catch up with the host vehicle before the lane change of the host vehicle is completed. At this time, for example, it may be necessary to cancel the lane change of the host vehicle.

[0005] An object of the present invention is to provide a lane change device that can surely complete a lane change of a host vehicle even when there is a following vehicle approaching the host vehicle at high speed.

[0006] The lane change device according to the present invention is a device that executes lane change control for changing the lane of the host vehicle to an adjacent lane. The lane change device according to the present invention estimates the possibility of a following vehicle catching up with the host vehicle, which is a following vehicle traveling so as to approach the host vehicle from behind the host vehicle and traveling in an adjacent lane in which the host vehicle is to be changed lanes by the lane change control. Then, the lane change device according to the present invention sets a target lane change time, which is a time from when the lane change control of the host vehicle starts to when the lane change to the adjacent lane is completed, as a shorter time as the possibility of the following vehicle catching up is higher, and performs the lane change of the host vehicle to the adjacent lane by the lane change control so that the lane change to the adjacent lane is completed within the set target lane change time. Furthermore, the host vehicle is equipped with a peripheral information detection device that detects information on the periphery of the host vehicle. And when a first condition that there is no following vehicle and the detection accuracy of the peripheral information detection device is equal to or lower than a predetermined accuracy is satisfied, the lane change device according to the present invention determines that the following vehicle may catch up with the host vehicle. When it is determined that the following vehicle may catch up with the host vehicle due to the satisfaction of the first condition, a predetermined first numerical value is added as a following vehicle catch-up possibility level which is a level indicating the possibility of the following vehicle catching up. The higher the following vehicle catch-up possibility level is, the shorter the target lane change time is set.

[0007] According to this, the higher the possibility of the following vehicle catching up, the shorter the time is set as the target lane change time, and the lane change of the host vehicle to the adjacent lane by the lane change control is performed so that the lane change is completed within the target lane change time. Therefore, even when there is a following vehicle approaching the host vehicle at high speed, the lane change of the host vehicle can be surely completed. In addition, when a second condition that there is no following vehicle and the traveling speed of the host vehicle is slower than a first speed or more than a regulated speed applicable to the host vehicle is satisfied, the lane change device according to the present invention determines that the following vehicle may catch up with the host vehicle. When it is determined that the following vehicle may catch up with the host vehicle due to the satisfaction of the second condition, it may be configured to add a predetermined second numerical value as the following vehicle catch-up possibility level. Also, when a third condition that there is no following vehicle and the distance between the traffic jam occurrence location in front of the host vehicle and the host vehicle is equal to or less than a predetermined distance is satisfied, the lane change device according to the present invention determines that the following vehicle may catch up with the host vehicle. When it is determined that the following vehicle may catch up with the host vehicle due to the satisfaction of the third condition, it may be configured to add a predetermined third numerical value as the following vehicle catch-up possibility level. Also, when a fourth condition that there is no following vehicle and the traveling speed of the host vehicle is faster than a second speed or more than the traveling speed of the preceding vehicle is satisfied, the lane change device according to the present invention determines that the following vehicle may catch up with the host vehicle. When it is determined that the following vehicle may catch up with the host vehicle due to the satisfaction of the fourth condition, it may be configured to add a predetermined fourth numerical value as the following vehicle catch-up possibility level. Further, when a fifth condition that there is no following vehicle, the host vehicle is traveling in a driving lane, and the adjacent lane is a passing lane is satisfied, it is determined that the following vehicle may catch up with the host vehicle. When it is determined that the following vehicle may catch up with the host vehicle due to the satisfaction of the fifth condition, a predetermined fifth numerical value may be added as the following vehicle catch-up possibility level.

[0008] The components of the present invention are not limited to the embodiments of the present invention described below with reference to the drawings. Other objects, other features, and attendant advantages of the present invention will be easily understood from the description of the embodiments of the present invention.

Brief Description of the Drawings

[0009]

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[0010] Hereinafter, a lane change device according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, a lane change device 10 according to an embodiment of the present invention is mounted on a host vehicle 100. In the following description, the driver of the host vehicle 100 is referred to as "driver DR".

[0011] <ecu> The lane change device 10 is equipped with an ECU 90. ECU is an abbreviation for Electronic Control Unit. The ECU 90 mainly comprises a microcomputer. The microcomputer includes a CPU, ROM, RAM, non-volatile memory, interface, etc. The CPU is adapted to realize various functions by executing instructions, programs or routines stored in the ROM.

[0012] <Traveling device> Furthermore, a traveling device 20 is mounted on the host vehicle 100. The traveling device 20 includes a driving device 21, a braking device 22, and a steering device 23.

[0013] <Driving device> The driving device 21 is a device that outputs a driving torque (driving force) added to the host vehicle 100 to make the host vehicle 100 travel, and is, for example, an internal combustion engine and a motor, etc. The driving device 21 is electrically connected to the ECU 90. The ECU 90 can control the driving torque output from the driving device 21 by controlling the operation of the driving device 21.

[0014] <Braking device> The braking device 22 is a device that outputs a braking torque (braking force) added to the host vehicle 100 to brake the host vehicle 100, and is, for example, a brake device. The braking device 22 is electrically connected to the ECU 90. The ECU 90 can control the braking torque output from the braking device 22 by controlling the operation of the braking device 22.

[0015] <Steering device> The steering device 23 is a device that outputs a steering torque (steering force) added to the host vehicle 100 to steer the host vehicle 100, and is, for example, a power steering device. The steering device 23 is electrically connected to the ECU 90. The ECU 90 can control the steering torque output from the steering device 23 by controlling the operation of the steering device 23.

[0016] <Sensor, etc.> Furthermore, the host vehicle 100 is equipped with an accelerator pedal 31, an accelerator pedal operation amount sensor 32, a brake pedal 33, a brake pedal operation amount sensor 34, a steering wheel 35, a steering shaft 36, a steering angle sensor 37, a steering torque sensor 38, a lane keeping request switch 41, a lane change request switch 42, a vehicle speed detection device 51, a GPS device 52, a surrounding information detection device 60, and a road information detection device 70.

[0017] <Accelerator pedal operation amount sensor> The accelerator pedal operation amount sensor 32 is a sensor that detects the operation amount of the accelerator pedal 31 and is electrically connected to the ECU 90. The accelerator pedal operation amount sensor 32 transmits information on the detected operation amount of the accelerator pedal 31 to the ECU 90. The ECU 90 acquires the operation amount of the accelerator pedal 31 as the accelerator pedal operation amount AP based on that information. When lane change control described later is not being executed, the ECU 90 executes normal driving control. During the execution of that normal driving control, the ECU 90 acquires a required driving torque (required driving force) based on the accelerator pedal operation amount AP and the host vehicle speed V100 (the traveling speed of the host vehicle 100), and controls the operation of the drive device 21 so that the required driving torque is output from the drive device 21.

[0018] <Brake pedal operation amount sensor> The brake pedal operation amount sensor 34 is a sensor that detects the operation amount of the brake pedal 33 and is electrically connected to the ECU 90. The brake pedal operation amount sensor 34 transmits information on the detected operation amount of the brake pedal 33 to the ECU 90. The ECU 90 acquires the operation amount of the brake pedal 33 as the brake pedal operation amount BP based on that information. As described above, when lane change control described later is not being executed, the ECU 90 executes normal driving control. During the execution of that normal driving control, the ECU 90 acquires a required braking torque (required braking force) based on the brake pedal operation amount BP, and controls the operation of the braking device 22 so that the required braking is output from the braking device 22.

[0019] <Steering angle sensor> The steering angle sensor 37 is a sensor that detects the rotation angle of the steering shaft 36 with respect to the neutral position, and is electrically connected to the ECU 90. The steering angle sensor 37 transmits the detected rotation angle information of the steering shaft 36 to the ECU 90. The ECU 90 acquires the rotation angle of the steering shaft 36 as the steering angle θs based on that information.

[0020] <Steering torque sensor> The steering torque sensor 38 is a sensor that detects the torque input by the driver DR to the steering shaft 36 via the steering wheel 35, and is electrically connected to the ECU 90. The steering torque sensor 38 transmits the detected torque information to the ECU 90. The ECU 90 acquires the torque (driver input torque) input by the driver DR to the steering shaft 36 via the steering wheel 35 based on that information. As described above, when the lane change control described later is not being executed, the ECU 90 executes normal driving control. During the execution of this normal driving control, the ECU 90 acquires the required steering torque based on the steering angle θs, the driver input torque, and the vehicle speed V100 (the traveling speed of the host vehicle 100), and controls the operation of the steering device 23 so that the required steering torque is output from the steering device 23.

[0021] <Lane keeping request switch> The lane keeping request switch 41 is a switch operated by the driver DR to request the execution of the lane keeping control described later, and is electrically connected to the ECU 90. When the lane keeping request switch 41 is operated and set to the on position, the ECU 90 determines that the execution of the lane keeping control has been requested.

[0022] <Lane change request switch> The lane change request switch 42 is a switch operated by the driver DR to request the execution of lane change control described later. For example, it is a turn signal lever operated by the driver DR to blink the direction indicator of the host vehicle 100. The lane change request switch 42 is electrically connected to the ECU 90. When the lane change request switch 42 is operated and set to a position requesting a lane change of the host vehicle 100 from the traveling lane (own lane LN_O) to the adjacent lane on the right side, the ECU 90 determines that the execution of lane change control for changing the lane of the host vehicle 100 to the adjacent lane on the right side of the own lane LN_O is requested. When the lane change request switch 42 is operated and set to a position requesting a lane change to the adjacent lane on the left side of the own lane LN_O, the ECU 90 determines that the execution of lane change control for changing the lane of the host vehicle 100 to the adjacent lane on the left side of the own lane LN_O is requested. When the lane change request switch 42 is a turn signal lever, if the state where the turn signal lever is operated in the clockwise direction continues for a predetermined time, the ECU 90 determines that the execution of lane change control for changing the lane of the host vehicle 100 to the adjacent lane on the right side of the own lane LN_O is requested. If the state where the turn signal lever is operated in the counterclockwise direction continues for a predetermined time, the ECU 90 determines that the execution of lane change control for changing the lane of the host vehicle 100 to the adjacent lane on the left side of the own lane LN_O is requested.

[0023] <Vehicle speed detection device> The vehicle speed detection device 51 is a device that detects the vehicle speed (own vehicle speed V100) of the host vehicle 100. For example, it is a wheel speed sensor. The vehicle speed detection device 51 is electrically connected to the ECU 90. The vehicle speed detection device 51 transmits the detected vehicle speed information of the host vehicle 100 to the ECU 90. The ECU 90 acquires the own vehicle speed V100 based on that information.

[0024] <GPS device> The GPS device 52 is a device that receives a so-called GPS signal and is electrically connected to the ECU 90. The ECU 90 acquires a GPS signal via the GPS device 52. The ECU 90 can acquire the current position P100 of the host vehicle 100 based on the acquired GPS signal.

[0025] <Peripheral Information Detection Device> The peripheral information detection device 60 is a device that detects information on the periphery of the host vehicle 100. In this example, it includes a radio wave sensor 61 and an image sensor 62. The radio wave sensor 61 is, for example, a radar sensor (such as a millimeter wave radar). The image sensor 62 is, for example, a camera. Note that the peripheral information detection device 60 may also include a sound wave sensor such as an ultrasonic sensor (clearance sonar) or an optical sensor such as a lidar (LiDAR).

[0026] <Radio Wave Sensor> The radio wave sensor 61 is electrically connected to the ECU 90. The radio wave sensor 61 transmits radio waves and receives radio waves (reflected waves) reflected by an object. The radio wave sensor 61 transmits information (detection result) related to the transmitted radio waves and the received radio waves (reflected waves) to the ECU 90. In other words, the radio wave sensor 61 detects an object existing around the host vehicle 100 and transmits information (detection result) related to the detected object to the ECU 90. The ECU 90 can obtain information (peripheral detection information IS) related to an object existing around the host vehicle 100 based on this information (radio wave information). Note that in this example, the object includes vehicles, motorcycles, bicycles, and people, etc.

[0027] <Image Sensor> The image sensor 62 is also electrically connected to the ECU 90. The image sensor 62 captures an image of the periphery of the host vehicle 100 and transmits information related to the captured image to the ECU 90. The ECU 90 can obtain information (peripheral detection information IS) related to the periphery of the host vehicle 100 based on this information (camera image information).

[0028] <Road Information Detection Device> The road information detection device 70 includes a receiving device 71 and a map information database 72.

[0029] <Receiving Device> The receiving device 71 is a device that receives a wireless signal from the outside and is electrically connected to the ECU 90. The ECU 90 obtains a wireless signal from the outside via the receiving device 71.

[0030] <Map information database> The map information database 72 is a database that stores map information including "information on regulated speed" and "information on road type", and is electrically connected to the ECU 90. The ECU 90 can acquire information on the regulated speed currently applied to the host vehicle 100 and the type of road on which the host vehicle 100 is currently traveling from the current position P100 of the host vehicle 100.

[0031] <Outline of operation of lane change device> Next, the outline of the operation of the lane change device 10 will be described.

[0032] <Lane change control> When execution of lane change control is requested, the lane change device 10 executes the lane change control on the condition that the prohibition condition CF described later is not satisfied. In this example, the fact that lane keeping control is being executed is not a condition for executing lane change control, but this may be used as a condition. The lane keeping control is a control for maintaining the travel of the host vehicle 100 within the host lane LN_O by recognizing the center line of the host lane LN_O based on the surrounding detection information IS and steering the host vehicle 100 to travel along the center line. The center line of the host vehicle 100 can be recognized based on the surrounding detection information IS.

[0033] As shown in FIG. 2, the lane change control is a control including a lane change travel process for automatically changing the lane of the host vehicle 100 to an adjacent lane (adjacent lane) to the host lane LN_O. FIG. 2 shows a scene where execution of lane change control for changing the lane of the host vehicle 100 to the adjacent lane (in the example shown in FIG. 2, the second lane LN2) on the right side of the host lane LN_O (in the example shown in FIG. 2, the first lane LN1) is requested. The lane change device 10 recognizes the host lane LN_O and the adjacent lane based on the surrounding detection information IS. In FIG. 2, the reference sign LN3 indicates the lane adjacent to the right of the second lane LN2.

[0034] The lane change control executed by the lane change device 10 will be described below. In the following description, the lane adjacent to the own lane LN_O in which the own vehicle 100 is to be changed by the lane change control is referred to as the "target lane LN_T".

[0035] When the execution of the lane change control is requested while the lane keeping control is being executed, the lane change device 10 starts the lane change control. When the lane change device 10 starts the lane change control, it first determines whether or not the prohibition condition CF is satisfied. The prohibition condition CF is a condition that is satisfied when it is determined that the lane change of the own vehicle 100 cannot be safely performed in view of the situation around the own vehicle 100.

[0036] In this example, as shown in FIG. 3, the prohibition condition CF is satisfied when there is a parallel vehicle 200 in the target lane LN_T (in the example shown in FIG. 3, the second lane LN2). In this example, the parallel vehicle 200 is another vehicle existing within a predetermined range AR set on the target lane LN_T side of the own vehicle 100. The predetermined range AR is a rectangular range in the horizontal plane, the width in the lateral direction thereof is equal to the width of the target lane LN_T, and the length in the longitudinal direction thereof is longer than the total length of the own vehicle 100. When there is another vehicle within the range of the length, it is presumed that the other vehicle hinders the safe lane change of the own lane LN_O to the target lane LN_T. The lane change device 10 recognizes the parallel vehicle 200 based on the surrounding detection information IS.

[0037] When the lane change device 10 determines that the prohibition condition CF is satisfied, it ends the lane change control. In this case, the lane change driving process is not performed, and thus, the lane change of the own vehicle 100 to the target lane LN_T is not performed.

[0038] On the one hand, when the lane change device 10 determines that the prohibition condition CF is not satisfied, it determines whether there is a following vehicle 200R in the target lane LN_T. In this example, the following vehicle 200R is another vehicle existing behind the host vehicle 100 as shown in FIG. 4. The lane change device 10 recognizes the following vehicle 200R based on the surrounding detection information IS. At this time, since the prohibition condition CF is not satisfied, the lane change device 10 is substantially determining whether there is a following vehicle 200R that does not exist within the predetermined range AR in the target lane LN_T.

[0039] When the lane change device 10 determines that the following vehicle 200R exists, it sets the target lane change time TLCtgt to the reference time TLCbase. The target lane change time TLCtgt is the time required to complete the lane change of the host vehicle 100 to the target lane LN_T after starting the lane change driving process.

[0040] When the lane change device 10 sets the target lane change time TLCtgt, as shown in FIG. 5, it sets the route for driving the host vehicle 100 to complete the lane change within the target lane change time TLCtgt as the target lane change route Rtgt.

[0041] When the lane change device 10 sets the target lane change route Rtgt, it starts a lane change driving process to control the operation of the driving device 20 so that the host vehicle 100 travels along the target lane change route Rtgt.

[0042] When the lane change of the host vehicle 100 is completed, the lane change device 10 ends the lane change driving process, thereby ending the lane change control. In this example, when the lane change control is ended, the lane keeping control is started.

[0043] On the one hand, when there is no trailing vehicle 200R, even if the reference time TLCbase is set to the target lane change time TLCtgt and the lane change driving process is started, it can be considered that the lane change of the host vehicle 100 to the target lane LN_T can be performed safely. However, for the following reasons, the lane change device 10 sets the target lane change time TLCtgt according to the trailing vehicle catching-up possibility level LVrsk and executes the lane change driving process.

[0044] That is, there is a trailing vehicle 200R that is traveling so as to approach the host vehicle 100 at high speed on the target lane LN_T. However, in a scenario where the trailing vehicle 200R is traveling at a very far distance from the host vehicle 100, the trailing vehicle 200R is not detected by the surrounding information detection device 60. Therefore, the lane change device 10 determines that there is no trailing vehicle 200R. In such a scenario, if the reference time TLCbase is set to the target lane change time TLCtgt and the lane change driving process is started just because there is no trailing vehicle 200R, before the lane change of the host vehicle 100 to the target lane LN_T is completed, the trailing vehicle 200R will catch up with the host vehicle 100, and the once-started lane change driving process will have to be aborted to ensure the safety of the host vehicle 100.

[0045] For example, when the host vehicle speed V100 is slower than the regulated speed Vreg applied to the host vehicle 100 at that time by a certain speed or more, if the lane change driving process is started just because there is no trailing vehicle 200R, there is a possibility that the host vehicle 100 will be caught up by the trailing vehicle 200R before the lane change of the host vehicle 100 is completed. Therefore, when the host vehicle speed V100 is slower than the regulated speed Vreg applied to the host vehicle 100 at that time by a predetermined speed (first speed V1) or more, the lane change device 10 determines that there is a possibility that the trailing vehicle 200R will catch up with the host vehicle 100 before the lane change of the host vehicle 100 is completed after the start of the lane change driving process. In other words, the lane change device 10 determines that there is a possibility that the trailing vehicle 200R will be detected and the abort condition Ccan will be satisfied before the lane change of the host vehicle 100 is completed after the start of the lane change driving process.

[0046] In this example, when the own vehicle speed V100 is slower than the first speed V1 or more above the regulation speed Vreg applied to the own vehicle 100 at that time, the possibility that the following vehicle 200R catches up with the own vehicle 100 before the lane change of the own vehicle 100 is completed is numerically determined in advance. Then, when the lane change device 10 determines that the own vehicle speed V100 is slower than the regulation speed Vreg applied to the own vehicle 100 at that time by a predetermined speed (first speed V1) or more, it adds that numerical value as the following vehicle catching-up possibility level LVrsk.

[0047] In addition, the lane change device 10 recognizes the regulation speed Vreg applied to the own vehicle 100 based on the information related to the road signs included in the surrounding detection information IS (particularly, camera image information). Alternatively, the lane change device 10 specifies the current position P100 of the own vehicle 100 from the GPS signal, collates the specified current position P100 of the own vehicle 100 with the map information stored in the map information database 72, specifies the road on which the own vehicle 100 is traveling at that time, and can also recognize the regulation speed Vreg applied to the own vehicle 100 by reading the regulation speed Vreg set for that road from the map information database 72. Further, the lane change device 10 can also receive, by the receiving device 71, a radio signal representing the regulation speed Vreg transmitted from a transmitter (so-called roadside unit) installed beside the road on which the own vehicle 100 is traveling at that time, and recognize the regulation speed Vreg applied to the own vehicle 100 based on that radio signal.

[0048] Furthermore, when a traffic jam has occurred in front of the host vehicle 100 and the host vehicle 100 is approaching the traffic jam location, after starting the lane change driving process, a situation is assumed where the host vehicle 100 reaches the traffic jam location and must decelerate. In that case, there is a possibility that the host vehicle 100 will catch up with the following vehicle 200R before the lane change of the host vehicle 100 is completed. Therefore, when a traffic jam has occurred in front of the host vehicle 100, the lane change device 10 determines that there is a possibility that the following vehicle 200R will catch up with the host vehicle 100 before the lane change of the host vehicle 100 is completed after starting the lane change driving process when the distance D between the host vehicle 100 and the traffic jam location is equal to or less than a predetermined distance (traffic jam arrival distance Dth). In other words, the lane change device 10 determines that there is a possibility that the following vehicle 200R will be detected and the stop condition Ccan will be satisfied before the lane change of the host vehicle 100 is completed after starting the lane change driving process.

[0049] In this example, when the distance D between the host vehicle 100 and the traffic jam location is equal to or less than the traffic jam arrival distance Dth, the possibility that the following vehicle 200R will catch up with the host vehicle 100 before the lane change of the host vehicle 100 is completed is quantified in advance. Then, when the lane change device 10 determines that the distance D between the host vehicle 100 and the traffic jam location is equal to or less than the traffic jam arrival distance Dth, that numerical value is added as the following vehicle catch-up possibility level LVrsk.

[0050] Note that the lane change device 10 receives, by the receiving device 71, a radio signal representing information related to the traffic jam location, identifies the traffic jam location based on the radio signal, and also identifies the current position P100 of the host vehicle 100 based on the GPS signal, and obtains the distance D between the host vehicle 100 and the traffic jam location from the identified traffic jam location and the current position P100 of the host vehicle 100.

[0051] Further, as shown in FIG. 6, when the leading vehicle 200F exists and the own vehicle speed V100 is faster than the vehicle speed V200 of the leading vehicle 200F by a certain speed or more, a situation is assumed where the own vehicle 100 must be decelerated after starting the lane change driving process. In that case, there is a possibility that the own vehicle 100 will catch up with the following vehicle 200R before the completion of the lane change of the own vehicle 100. Therefore, when the leading vehicle 200F exists and the own vehicle speed V100 is faster than the vehicle speed V200 of the leading vehicle 200F by a predetermined speed (second speed V2) or more, the lane change device 10 determines that there is a possibility that the following vehicle 200R will catch up with the own vehicle 100 before the completion of the lane change of the own vehicle 100 after the start of the lane change driving process. In other words, the lane change device 10 determines that there is a possibility that the following vehicle 200R will be detected and the stop condition Ccan will be satisfied before the completion of the lane change of the own vehicle 100 after the start of the lane change driving process.

[0052] In this example, when the own vehicle speed V100 is faster than the vehicle speed V200 of the leading vehicle 200F by the second speed V2 or more, the possibility that the following vehicle 200R will catch up with the own vehicle 100 before the completion of the lane change of the own vehicle 100 is quantified in advance. Then, when the lane change device 10 determines that the own vehicle speed V100 is faster than the vehicle speed V200 of the leading vehicle 200F by the second speed V2 or more, that numerical value is added as the following vehicle catching-up possibility level LVrsk.

[0053] Note that the lane change device 10 detects the leading vehicle 200F based on the surrounding detection information IS and acquires the vehicle speed V200 of the detected leading vehicle 200F.

[0054] Also, generally, the traveling speed of a vehicle traveling in the passing lane is faster than that of a vehicle traveling in the driving lane. Therefore, as shown in FIG. 7, when the host vehicle 100 is traveling in the driving lane (i.e., the first lane LN1) and the target lane LN_T is the passing lane (i.e., the second lane LN2), after starting the lane change driving process, there is a possibility that the host vehicle 100 will be overtaken by the following vehicle 200R before the completion of the lane change of the host vehicle 100. Therefore, when the host vehicle 100 is traveling in the driving lane and the target lane LN_T is the passing lane, the lane change device 10 determines that there is a possibility that the following vehicle 200R will overtake the host vehicle 100 before the completion of the lane change of the host vehicle 100 after the start of the lane change driving process. In other words, the lane change device 10 determines that there is a possibility that the following vehicle 200R will be detected and the stop condition Ccan will be satisfied before the completion of the lane change of the host vehicle 100 after the start of the lane change driving process.

[0055] In this example, when the host vehicle 100 is traveling in the driving lane and the target lane LN_T is the passing lane, the possibility that the following vehicle 200R will overtake the host vehicle 100 before the completion of the lane change of the host vehicle 100 is quantified in advance. Then, when the lane change device 10 determines that the host vehicle 100 is traveling in the driving lane and the target lane LN_T is the passing lane, the numerical value is added as the following vehicle overtaking possibility level LVrsk.

[0056] In addition, the lane change device 10 identifies the current position P100 of the host vehicle 100 based on the GPS signal, collates the identified current position P100 of the host vehicle 100 with the map information stored in the map information database 72, identifies the road on which the host vehicle 100 is traveling at that time, reads out the type of each lane provided on the road from the map information database 72, and determines whether the own lane LN_O is the driving lane and whether the target lane LN_T is the passing lane.

[0057] Also, if the detection accuracy of the surrounding information detection device 60 is maintained at a sufficient level, the trailing vehicle 200R detected by the surrounding information detection device 60 may not be detected by the surrounding information detection device 60 if the detection accuracy of the surrounding information detection device 60 is insufficient. In this case, if the lane change driving process is started just because it is determined that the trailing vehicle 200R does not exist, there is a possibility that the host vehicle 100 will be caught up by the trailing vehicle 200R before the completion of the lane change of the host vehicle 100. Therefore, the lane change device 10 performs a self-diagnosis of the detection accuracy of the surrounding information detection device 60, and if the detected accuracy obtained thereby is equal to or lower than a predetermined accuracy, after starting the lane change driving process, it is determined that there is a possibility that the trailing vehicle 200R will catch up with the host vehicle 100 before the completion of the lane change of the host vehicle 100. In other words, the lane change device 10 determines that there is a possibility that the trailing vehicle 200R will be detected and the stop condition Ccan will be satisfied before the completion of the lane change of the host vehicle 100 after starting the lane change driving process.

[0058] In this example, when the detection accuracy of the surrounding information detection device 60 is equal to or lower than a predetermined accuracy, the possibility that the trailing vehicle 200R will catch up with the host vehicle 100 before the completion of the lane change of the host vehicle 100 is quantified in advance. Then, when the lane change device 10 determines that the detection accuracy of the surrounding information detection device 60 is equal to or lower than a predetermined accuracy, that numerical value is added as the trailing vehicle catching-up possibility level LVrsk.

[0059] When the lane change device 10 calculates the trailing vehicle catching-up possibility level LVrsk as described above, the higher the height of the trailing vehicle catching-up possibility level LVrsk, the shorter the time than the reference time TLCbase is set as the target lane change time TLCtgt.

[0060] When the lane change device 10 sets the target lane change time TLCtgt, a route for driving the host vehicle 100 to complete the lane change within the target lane change time TLCtgt is set as the target lane change route Rtgt.

[0061] When the lane change device 10 sets the target lane change route Rtgt, it starts a lane change driving process that controls the operation of the driving device 20 so that the host vehicle 100 travels along the target lane change route Rtgt.

[0062] When the lane change of the host vehicle 100 is completed, the lane change device 10 ends the lane change driving process, thereby ending the lane change control. As described above, in this example, when the lane change control is ended, the lane keeping control is started.

[0063] In addition, during the execution of the lane change driving process, when the lane change device 10 detects a following vehicle 200R approaching the host vehicle 100 and determines that it is preferable to abort the lane change driving process (that is, when the abort condition Ccan is satisfied), the lane change driving process is aborted.

[0064] In addition, although the above-described lane change device 10 sets a shorter time as the target lane change time TLCtgt as the following vehicle catching-up possibility level LVrsk is higher, it may be configured to set the target lane change time TLCtgt according to whether the following vehicle catching-up possibility level LVrsk is equal to or higher than a predetermined level LVth.

[0065] That is, when the lane change device 10 calculates the following vehicle catching-up possibility level LVrsk, it determines whether the following vehicle catching-up possibility level LVrsk is equal to or higher than a predetermined level LVth.

[0066] When the following vehicle catching-up possibility level LVrsk is equal to or higher than a predetermined level LVth, the lane change device 10 sets a predetermined time TLCshort shorter than the reference time TLCbase as the target lane change time TLCtgt.

[0067] On the other hand, when the following vehicle catching-up possibility level LVrsk is smaller than a predetermined level LVth, the lane change device 10 sets the reference time TLCbase as the target lane change time TLCtgt.

[0068] The above is an overview of the operation of the lane change device 10. According to this, the shorter time TLCrsk or TLCshort is set as the target lane change time TLCtgt as the following vehicle following possibility level LVrsk is higher, and the lane change control causes the host vehicle 100 to change lanes to an adjacent lane so that the lane change is completed at the target lane change time TLCtgt. Therefore, even when there is a following vehicle 200R approaching the host vehicle 100 at high speed, the lane change of the host vehicle 100 can be surely completed.

[0069] <Specific operation of the lane change device> Next, the specific operation of the lane change device 10 will be described. The CPU of the ECU 90 of the lane change device 10 is configured to execute the routine shown in FIG. 8 at a predetermined calculation cycle.

[0070] Therefore, at a predetermined timing, the CPU starts processing from step 800 in FIG. 8, advances the processing to step 805, and determines whether the value of the lane change condition flag XLC is "1". The lane change condition flag XLC is a flag indicating whether execution of lane change control is requested. Its value is set to "1" when execution of lane change control is requested, and is set to "0" when execution of lane change control is not requested.

[0071] If the CPU determines "Yes" in step 805, the processing advances to step 810, and it is determined whether the value of the lane change in progress flag XLCexe is "0". The lane change in progress flag XLCexe is a flag indicating whether the lane change traveling process is being executed. Its value is set to "1" when the lane change traveling process is being executed, and is set to "0" when the lane change traveling process is not being executed.

[0072] If the CPU determines "Yes" in step 810, it proceeds with the process to step 815 and determines whether the value of the prohibition condition flag XF is "0". The prohibition condition flag XF is a flag indicating whether the prohibition condition CF is satisfied. Its value is set to "1" when the prohibition condition CF is satisfied, and is set to "0" when the prohibition condition CF is not satisfied.

[0073] If the CPU determines "Yes" in step 815, it proceeds with the process to step 820 and determines whether there is a following vehicle 200R (whether the following vehicle 200R is detected).

[0074] If the CPU determines "Yes" in step 820, it proceeds with the process to step 825 and executes the routine shown in FIG. 9. Therefore, when the CPU proceeds with the process to step 825, it starts the process from step 900 in FIG. 9, proceeds with the process to step 905, and sets the reference time TLCbase as the target lane change time TLCtgt. Next, the CPU proceeds with the process to step 910 and sets the target lane change route Rtgt.

[0075] Next, the CPU proceeds with the process to step 915 and sets the value of the lane change driving start flag XLCstart to "1". The lane change driving start flag XLCstart is a flag indicating whether to start the lane change driving process. Its value is set to "1" when starting the lane change driving process, and is set to "0" when the lane change driving process is completed.

[0076] Next, the CPU proceeds with the process to step 920 and sets the value of the lane change driving in progress flag XLCexe to "1". Thereafter, the CPU proceeds with the process to step 895 in FIG. 8 via step 995 and temporarily ends this routine.

[0077] On the other hand, when the CPU determines "No" in step 820, the process proceeds to step 830 and executes the routine shown in FIG. 10 or FIG. 11. Therefore, when the CPU is configured to execute the routine shown in FIG. 10 when the process proceeds to step 830, when the process proceeds to step 830, the process starts from step 1000 in FIG. 10, advances the process to step 1005, and calculates the following vehicle catching-up possibility level LVrsk. Next, the CPU advances the process to step 1010 and sets the obtained time TLCrsk according to the following vehicle catching-up possibility level LVrsk as the target lane change time TLCtgt. Next, the CPU advances the process to step 1015 and sets the target lane change route Rtgt.

[0078] Next, the CPU advances the process to step 1020 and sets the value of the lane change driving start flag XLCstart to "1". Next, the CPU advances the process to step 1025 and sets the value of the lane change driving flag XLCexe to "1". Thereafter, the CPU advances the process to step 895 in FIG. 8 via step 1095 and temporarily ends this routine.

[0079] On the other hand, when the CPU is configured to execute the routine shown in FIG. 11 when the process proceeds to step 830, when the process proceeds to step 830, the process starts from step 1100 in FIG. 11, advances the process to step 1105, and calculates the following vehicle catching-up possibility level LVrsk. Next, the CPU advances the process to step 1111 and determines whether the following vehicle catching-up possibility level LVrsk is equal to or higher than a predetermined level LVth.

[0080] When the CPU determines "Yes" in step 1111, the process proceeds to step 1112 and sets a predetermined time TLCshort as the target lane change time TLCtgt. Next, the CPU proceeds to step 1115.

[0081] On the other hand, if the CPU determines "No" in step 1111, the process proceeds to step 1113, and the reference time TLCbase is set as the target lane change time TLCtgt. Then, the CPU proceeds with the process to step 1115.

[0082] When the CPU proceeds with the process to step 1115, it sets the target lane change route Rtgt. Then, the CPU proceeds with the process to step 1120 and sets the value of the lane change driving start flag XLCstart to "1". Next, the CPU proceeds with the process to step 1125 and sets the value of the lane change driving during flag XLCexe to "1". After that, the CPU proceeds with the process to step 895 in Figure 8 via step 1195 and temporarily ends this routine.

[0083] In addition, if the CPU determines "No" in step 805 or step 810 or step 815 in Figure 8, the process proceeds to step 895 and this routine is temporarily ended.

[0084] Furthermore, the CPU is configured to execute the routine shown in Figure 12 at a predetermined calculation cycle. Therefore, at a predetermined timing, the CPU starts the process from step 1200 in Figure 12, proceeds with the process to step 1205, and determines whether the value of the lane change driving start flag XLCstart is "1".

[0085] If the CPU determines "Yes" in step 1205, the process proceeds to step 1210, and it determines whether the value of the lane change driving cancellation flag XLCcan is "0". The lane change driving cancellation flag XLCcan is a flag indicating whether the cancellation condition Ccan has been satisfied after the start of the lane change driving process. Its value is set to "1" when the cancellation condition Ccan is satisfied after the start of the lane change driving process, and is set to "0" when the cancellation condition Ccan has not been satisfied after the start of the lane change driving process.

[0086] If the CPU determines "Yes" in step 1210, it advances the process to step 1215 and executes the lane change driving process. Next, the CPU advances the process to step 1220 and determines whether the lane change is completed.

[0087] If the CPU determines "Yes" in step 1220, it advances the process to step 1225 and ends the lane change driving process. Next, the CPU advances the process to step 1230 and sets the values of the lane change condition flag XLC, the lane change driving start flag XLCstart, the lane change driving in progress flag XLCexe, the lane change driving cancellation flag XLCcan, and the prohibition condition flag XF to "0" respectively. Then, the CPU advances the process to step 1295 and temporarily ends this routine.

[0088] On the other hand, if the CPU determines "No" in step 1220, it directly advances the process to step 1295 and temporarily ends this routine.

[0089] Also, if the CPU determines "No" in step 1210, it advances the process to step 1235 and cancels the lane change driving process. Next, the CPU advances the process to step 1240 and sets the values of the lane change condition flag XLC, the lane change driving start flag XLCstart, the lane change driving in progress flag XLCexe, the lane change driving cancellation flag XLCcan, and the prohibition condition flag XF to "0" respectively. Then, the CPU advances the process to step 1295 and temporarily ends this routine.

[0090] Also, if the CPU determines "No" in step 1205, it directly advances the process to step 1295 and temporarily ends this routine.

[0091] The above is the specific operation of the lane change device 10.

[0092] Note that the present invention is not limited to the above-described embodiment, and various modifications can be adopted within the scope of the present invention.

Explanation of Reference Numerals

[0093] 10…Lane change device, 20…Travel device, 42…Lane change request switch, 51…Vehicle speed detection device, 52…GPS device, 60…Peripheral information detection device, 61…Radio wave sensor, 62…Image sensor, 70…Road information detection device, 71…Receiving device, 72…Map information database, 90…ECU, 100…Own vehicle, 200R…Following vehicle< / ecu>

Claims

1. A lane change device that executes lane change control to cause a host vehicle to change lanes to an adjacent lane, a following vehicle that is traveling so as to approach the host vehicle from behind the host vehicle, and estimates the possibility of the following vehicle catching up with the host vehicle when the host vehicle changes lanes by the lane change control, the higher the possibility of the following vehicle catching up, the shorter the target lane change time, which is the time from the start of the lane change of the host vehicle by the lane change control until the completion of the lane change to the adjacent lane, is set, the lane change control is performed to change the lane of the host vehicle to the adjacent lane so that the lane change to the adjacent lane is completed within the set target lane change time. In a lane change device configured as described above, the host vehicle is equipped with a peripheral information detection device that detects information around the host vehicle, when a first condition that the following vehicle does not exist and the detection accuracy of the peripheral information detection device is equal to or lower than a predetermined accuracy is satisfied, it is determined that the following vehicle may catch up with the host vehicle, when it is determined that the following vehicle may catch up with the host vehicle due to the satisfaction of the first condition, a predetermined first numerical value is added as the following vehicle catch-up possibility level, which is a level indicating the possibility of the following vehicle catching up, the higher the following vehicle catch-up possibility level, the shorter the target lane change time is set. A lane change device configured as described above.

2. In the lane change device according to claim 1, when a second condition that the following vehicle does not exist and the traveling speed of the host vehicle is slower than a first speed or more than a regulated speed applied to the host vehicle is satisfied, it is determined that the following vehicle may catch up with the host vehicle, when it is determined that the following vehicle may catch up with the host vehicle due to the satisfaction of the second condition, a predetermined second numerical value is added as the following vehicle catch-up possibility level. A lane change device configured as described above.

3. In the lane change device according to claim 1, when a third condition that the following vehicle does not exist and the distance between the traffic jam occurrence location in front of the host vehicle and the host vehicle is equal to or less than a predetermined distance is satisfied, it is determined that the following vehicle may catch up with the host vehicle, When it is determined that there is a possibility that the following vehicle may catch up with the host vehicle due to the satisfaction of the third condition, a predetermined third numerical value is added as the following vehicle catch-up possibility level. A lane change device configured as described above.

4. In the lane change device according to Claim 1, when a fourth condition that the following vehicle does not exist and the traveling speed of the host vehicle is faster than the traveling speed of the preceding vehicle by a second speed or more is satisfied, it is determined that there is a possibility that the following vehicle may catch up with the host vehicle. When it is determined that there is a possibility that the following vehicle may catch up with the host vehicle due to the satisfaction of the fourth condition, a predetermined fourth numerical value is added as the following vehicle catch-up possibility level. A lane change device configured as described above.

5. In the lane change device according to Claim 1, when a fifth condition that the following vehicle does not exist and the host vehicle is traveling in a travel lane and the adjacent lane is a passing lane is satisfied, it is determined that there is a possibility that the following vehicle may catch up with the host vehicle. When it is determined that there is a possibility that the following vehicle may catch up with the host vehicle due to the satisfaction of the fifth condition, a predetermined fifth numerical value is added as the following vehicle catch-up possibility level. A lane change device configured as described above.

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